docs: def normalize_scheme(path, ext):
      """
      Normalize scheme for paths related to hdfs
      """
      path = addextension(path, ext)
  
      parsed = urlparse(path)
      if parsed.scheme:
          # this appears to already be a fully-qualified URI
          return path
      else:
          # this looks like a local path spec
          import os
          dirname, filename = os.path.split(path)
          if not os.path.isabs(dirname):
              # need to make relative local paths absolute
              dirname = os.path.abspath(dirname)
              path = os.path.join(dirname, filename)
          return "file://" + path